Hamilton on 2 November 1967 is said to have been the most famous by-election in modern Scottish history.
A dynamic Glasgow lawyer Winnie Ewing took a rock solid Labour seat with 42% of the vote on a massive swing and put the SNP -around since the 30's- on the British political map for the first time.
It shouldn't have been a shock. The Wilson Government was intensely unpopular. There was a sense of economic decline. And the SNP had done well in that May's council elections getting 30%.
Yet the unionist parties were bewildered and didn't know how to react. The Tories tried to portray it as a freak result. Yet their leader Edward Heath wasn't quite so sure. Indeed at the Scottish Conservative Conference in Perth he announced that the Tories now backed a devolved Scottish Assembly. This "Declaration of Perth" stunned the Tory grassroots.
Labour was more sanguine. Wilson thought the storm would blow over. So he kicked the whole issue into the long grass. In 1969 he appointed Lord Crowther to head a Royal Commission on the Constitution.
The in the 1970 election Ewing lost Hamilton. Elsewhere the SNP only won one seat, the Western Isles. It did win 13% of the vote -its best General Election performance yet- but there was a general acceptance that the bubble had burst!
Yet Dundee East and Govan were still to come!